Calculator



FIG. 1 is a top, rear, right side perspective view of a calculator, showing our new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a right side view, the left side view being a mirror image thereof;

FIG. 4 is a front elevational view thereof;

FIG. 5 is a rear elevational view thereof; and,

FIG. 6 is a bottom plan view thereof.

The broken lines depict environmental subject matter only and form no part of the claimed design. 

The ornamental design for a calculator, as shown and described. 